2021-06-08 15:37:31

by Colin King

Subject: [PATCH][next] etfilter: fix array index out-of-bounds error

From: Colin Ian King <[email protected]>

Currently the array net->nf.hooks_ipv6 is accessed by index hook
before hook is sanity checked. Fix this by moving the sanity check
to before the array access.

Addresses-Coverity: ("Out-of-bounds access")
Fixes: e2cf17d3774c ("netfilter: add new hook nfnl subsystem")
Signed-off-by: Colin Ian King <[email protected]>
---
net/netfilter/nfnetlink_hook.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/netfilter/nfnetlink_hook.c b/net/netfilter/nfnetlink_hook.c
index 04586dfa2acd..58fda6ac663b 100644
--- a/net/netfilter/nfnetlink_hook.c
+++ b/net/netfilter/nfnetlink_hook.c
@@ -181,9 +181,9 @@ nfnl_hook_entries_head(u8 pf, unsigned int hook, struct net *net, const char *de
hook_head = rcu_dereference(net->nf.hooks_ipv4[hook]);
break;
case NFPROTO_IPV6:
- hook_head = rcu_dereference(net->nf.hooks_ipv6[hook]);
if (hook >= ARRAY_SIZE(net->nf.hooks_ipv6))
return ERR_PTR(-EINVAL);
+ hook_head = rcu_dereference(net->nf.hooks_ipv6[hook]);
break;
case NFPROTO_ARP:
#ifdef CONFIG_NETFILTER_FAMILY_ARP
--
2.31.1

2021-06-09 19:36:41

by Pablo Neira Ayuso

Subject: Re: [PATCH][next] etfilter: fix array index out-of-bounds error

On Tue, Jun 08, 2021 at 04:34:08PM +0100, Colin King wrote:
> From: Colin Ian King <[email protected]>
>
> Currently the array net->nf.hooks_ipv6 is accessed by index hook
> before hook is sanity checked. Fix this by moving the sanity check
> to before the array access.

Applied, thanks.